Introduction

In previous chapters, we created different Pods, managed their life cycle manually, and added metadata (labels or annotations) to them to help organize and identify various Pods. In this chapter, we will take a look at a few Kubernetes objects that help you manage several replica Pods declaratively.

When deploying your application in production, there are several reasons why you would want to have more than one replica of your Pods. Having more than one replica ensures that your application continues to work in cases where one or more Pods fail. In addition to handling failures, replication also allows you to balance the load across the different replicas so that one Pod is not overloaded with a lot of requests, thereby allowing you to easily serve higher traffic than what a single Pod can serve.

Kubernetes supports different controllers that you can use for replication, such as ReplicaSets, Deployments, DaemonSets, StatefulSets, and Jobs. A controller is an object...